This video will demonstrate the procedure for the bone marrow aspiration and bone marrow biopsy from the posterior iliac crest.

Obtaining a bone marrow aspirate and core biopsy is often necessary when evaluating a patient who has a hematologic abnormality.

Examining bone marrow is also useful in the diagnosis of metastatic spread of non-hematologic malignancies and to diagnose metabolic disorders.

Gather the necessary equipment prior to performing the procedure.

You will require equipment for sterile skin preparation and a sterile field, one percent lidocaine buffered with sterile sodium bicarbonate, a 25 gauge needle and five-milliliter syringe, a bone marrow aspiration needle, a bone marrow biopsy needle, two-thirty milliliter syringes,sterile heparin sulfate, sterile gauze, and bandage. Several types of bone marrow biopsy needles are commercially available.

This video will demonstrate the use of the Jamshidi needle for obtaining a core biopsy.

There should be an additional team member present responsible for the immediate preparation of specimens.

As you prepare to perform this procedure, ensure that there are no contrary indications that consent has been obtained after explaining the procedure and that you have gathered the necessary equipment.

Bone marrow aspiration and biopsy should not be performed if an infection of the bone is suspected. As the risk of bleeding with this procedure is low, thrombocytopenia is generally not a contrary indication.

The posterior iliac crest is the most common site used to obtain bone marrow. This site can be reached with the patient in either the prone or decubitus position. This video will demonstrate the decubitus position. The patient should be positioned in the right or left lateral decubitus position with knees flexed, the posterior iliac crest is located at the center of the posterior superior iliac spine. With the patient lying on his or her side, palpate the posterior iliac crest.

If there is a reason not to use the posterior iliac crest. Bone marrow aspiration from the anterior iliac crest may be performed. Though the sternum can be used to obtain a bone marrow aspiration under exceptional circumstances it is not suitable for a bone marrow biopsy. Once the patient is positioned the site should be prepared with a chlorhexidine scrub and draped with sterile towels, as with all invasive procedures, meticulous care should be taken to minimize the risk of infection. While the invasiveness of the procedure may not necessitate a sterile gown and mask, the operator should add on sterile gloves and adhere to strict standard precautions.

At a minimum, the patient will need medication for procedure pain. The needs of the patient should be considered and discussed in advance. Local or systematic anesthesia or both may be indicated. Some patients may need medications to induce conscious sedation. Deep sedation is generally recommended for all pediatric patients. A separate clinician should be responsible for monitoring the patient's sedation and the physiological status during the bone marrow procedure.

After sterile preparation, one percent lidocaine should be slowly injected to raise a wheel over the biopsy site. Then infiltrate the periosteum with two to five milliliters of buffered lidocaine.

In the awake patient, ensure the adequacy of local anesthesia by gently tapping the periosteum with the tip of the needle used to deliver the anesthetic. Be sure that you have prepared the appropriate number of thirty-milliliter syringes with and without heparin prior to starting the bone marrow aspiration. Inspect the bone marrow aspiration needle and move the plastic guard if one is present.

Hold the needle horizontally and insert it into the skin over the posterior iliac crest. Advanced the needle until it contacts the bone, to engage the bone, the needle should be rotated alternately clockwise and counterclockwise while applying the steady pressure, when the marrow cavity is entered, a sudden decrease in resistance is usually felt. The ilium is a large bone and the marrow space should be located easily.

However, the angle of entry is important. In general, the needle should be advanced at an angle completely perpendicular to the bony prominence of the iliac crest. Once the needle is through the cortex and the marrow cavity is entered, the needle should stay in place without being held, next remove the style attach a thirty-milliliter syringe without heparin, and aspirate one milliliter of marrow with a firm pull since the aspiration itself can be particularly painful.

It is prudent to warn the conscious patient before you aspirate. Note that you may hand a syringe to an assistant or pathologist taking care to maintain sterility. The non-heparinized aspirate should be used to prepare specimen slides. The adequacy of the specimen can be verified by the presence of bony spicules in the sample. Next, aspirate marrow into syringe one-milliliter heparin as needed for diagnostic tests. Remove the aspiration needle and apply pressure with sterile gauze until you are ready to perform the biopsy.

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A bone marrow biopsy is often done following a bone marrow aspiration. Maintain sterility, obtain a bone marrow biopsy needle. Holding the needle between your palm and index finger, insert the needle into the patient's skin and advance until it touches the bone. If an aspirate has been performed, the same entry site through the skin may be used for the biopsy. However, a skin incision may be indicated if only a bone marrow biopsy is being done or after an aspirate to allow for entry of the larger biopsy needle. While applying steady pressure, advance the needle with a style in place into the cortex by rotating back and forth. The biopsy needle should be inserted into the bone at a slightly different angle than a previously performed aspiration.

Once the needle is anchored in the bone, remove the stylet. Continue to advance the needle one to two centimeters into the marrow cavity with a back and forth rotating motion. The stylet may be reinserted to determine the length of the biopsy specimen in the needle. In order to remove the needle, it must be detached from the surrounding marrow and bone. Do not pull the needle straight out as doing so may allow the specimen to remain attached to the surrounding marrow and prevent it from being removed from the needle. Rotate the needle three hundred and sixty degrees several times in both clockwise and counterclockwise directions prior to removal. The needle should then be rocked back and forth to ensure detachment of the specimen from the surrounding marrow. Slowly pull the needle out while continuing to rotate. Remove the specimen from the needle by inserting a sterile probe into the distal end of the needle and push the specimen through the hub onto sterile gauze or a slide.

Inspect the specimen for the adequacy of marrow. Apply pressure to the biopsy site with the gauze until any bleeding stops and cover with a bandage or pressure dressing. Instruct the patient that the dressing can be removed the next day and that they should protect the wound from contact with water until a firm scrab is formed. Any substantial bleeding from the side should be reported to the physician. The patient may experience soreness at the biopsy site for one to two days that are best controlled with oral analgesics. The patient should be instructed that anything out of the ordinary should be prompt physician evaluation.

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Occasionally, bone marrow cannot be aspirated. A dry aspiration may be due to an inadequate angle of the needle insertion. In this case, repeat needle placement should be performed. A dry tap can also be due to underlying bone marrow diseases, such as myelofibrosis or certain hematologic malignancies. Remove the biopsy needle without breaking off the core specimen is a common problem. In this case, reinsert the biopsy needle to ensure that the specimen has been detached from the surrounding before removing the needle, and be sure to remove the biopsy needle slowly while continuing to rotate the needle. If the specimen is too small or contains too much cortex and too little marrow, consider obtaining an additional biopsy specimen.

A technician is often available to assist with the preparation of the bone marrow aspirate and bone marrow biopsy. Aspirate smears may be prepared at the bedside from unheparinized bone marrow aspirate. This should be done quickly to avoid clotting of the specimen. Bone marrow aspirate may also be sent to the lab for further analysis in heparinized syringes. The core biopsy specimen should be collected onto a sterile gauze or a slide and inspected for the adequacy of marrow. The biopsy specimen should be at least two centimeters in length in an adult patient. If desired, a touch prep of the biopsy core can be made. The touch prep can allow for morphological analysis similar to that obtained with an aspirate. After the touch prep, the bone marrow biopsy specimen should be placed in a proper sterile specimen container.

A bone marrow aspirate and biopsy are useful tools in assessing a variety of hematologic oncology and other disease processes that may involve the marrow space. Attention to detail and care for the patient can field valuable information that is not available by routine blood studies.